Should I modifymy IDE once I am changing from Arduino Nano to ProMini ?

I made an IDE which combines the DHT, LDR and a RELAY "mysensor" libraries together in one single code. Then I uploaded it to my Arduino Nano for testing, everything went smoothly and fine and I got all the readings on my HA.

The problem started once I uploaded the same code to my Arduino Pro mini (I changed the board and port before uploading), and then for some reason, it keeps telling "It failed to read temp/hum from DHT". Believe me I doubled checked pin numbers, wires, and everything I still get the same error. Even when I changed to another Promini, I got the same error. And to add to my confusion, without changing anything, once I put the Nano back on, everything started to work and it could read data from DHT !

So now I have two questions in my head;

Is it possible that some "mysensors" libraries are incompatible with certain boards ?

Simply, is there any difference between pin D3 on a Promini and a Nano ? (maybe ProMini can't provide the current required by DHT ... ?)

Not a chance that it is the bad quality wire, cause Nano works on the very same wiring.

Following your suggestion, I tested the Pro mini with the example sketch of dht lib. I get a weired outputs on my serial port (baud rate is matching to the defined rate on sketch, I even tried all other baud rates anyway ...)